diff --git a/src/mame/drivers/lucky74.c b/src/mame/drivers/lucky74.c
index 68c04e24646..26a5cd19e42 100644
--- a/src/mame/drivers/lucky74.c
+++ b/src/mame/drivers/lucky74.c
@@ -791,6 +791,11 @@
 #include "lucky74.lh"
 #include "includes/lucky74.h"
 
+void lucky74_state::machine_reset()
+{
+	m_copro_sm7831 = 0;
+	m_usart_8251 = 0;
+}
 
 /*****************************
 *    Read/Write  Handlers    *
diff --git a/src/mame/includes/lucky74.h b/src/mame/includes/lucky74.h
index 2679156bc94..c1d6cb46bbf 100644
--- a/src/mame/includes/lucky74.h
+++ b/src/mame/includes/lucky74.h
@@ -42,6 +42,7 @@ public:
 	TILE_GET_INFO_MEMBER(get_fg_tile_info);
 	TILE_GET_INFO_MEMBER(get_bg_tile_info);
 	virtual void video_start();
+	virtual void machine_reset();
 	virtual void sound_start();
 	virtual void palette_init();
 	UINT32 screen_update_lucky74(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);